From 79183d3c3ef509543b47acc1b5e48e4285734f36 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Reimar=20D=C3=B6ffinger?= <Reimar.Doeffinger@gmx.de>
Date: Sun, 31 May 2009 18:17:33 +0000
Subject: [PATCH] mszh decompression: add a special case for an all-0 mask,
 i.e. 32 uncompressed bytes in a row. About 15% faster mszh_decomp on an Atom
 N270 for http://samples.mplayerhq.hu/V-codecs/mszh-zlib/avimzsh_sample.avi

Originally committed as revision 19068 to svn://svn.ffmpeg.org/ffmpeg/trunk
---
 libavcodec/lcldec.c | 7 +++++++
 1 file changed, 7 insertions(+)

diff --git a/libavcodec/lcldec.c b/libavcodec/lcldec.c
index bc7e11d267..a6e348bd8e 100644
--- a/libavcodec/lcldec.c
+++ b/libavcodec/lcldec.c
@@ -102,6 +102,13 @@ static unsigned int mszh_decomp(const unsigned char * srcptr, int srclen, unsign
         maskbit >>= 1;
         if (!maskbit) {
             mask = *srcptr++;
+            while (!mask) {
+                if (destptr_end - destptr < 32 || srcptr_end - srcptr < 32) break;
+                memcpy(destptr, srcptr, 32);
+                destptr += 32;
+                srcptr += 32;
+                mask = *srcptr++;
+            }
             maskbit = 0x80;
         }
     }